Porsche Enthusiasts Club Forum

Does anyone suffer this problem and have a possible solution?

I have a 1991 944 S2. It runs really well and is in fantastic condition but in these winter months a small niggle has come to light.
I always start her up and let her warm up before I venture out and the engine gets nice and toasty as to be expected.
Yet when I get out on the open road the engine temperature drops right off so much so that the hot air blower starts blowing luke warm air into the car.
Now it's not a major problem but last night I drove back from the New Forest to Harrow late at night and it took a good two and a half hours.
I was frozen by the time I got home and had one very unimpressed girlfriend in the passenger seat who then spent about two hours hugging the radiator in the living room.

Is this common or does any one else suffer from it?

Turn the central heating off or take the radiator out of the living room.

What was the water temp gauge reading?

Sounds like thermostat to me, a swine of a job. Brass thermostat, with rubber washer, alloy housing & a steel circlip which needs the hands of a gynaecologist to get at. Vorsprung Technic my eye!

Either needs bled or needs the thermisters replaced. There are 3. Put on the demister and see if it heats up. If it does you need to replace the thermisters or the main control unit itself.

If still cold with demister on it probably needs bled, thermostat replaced or both!

Stuart

Agree with Jim. If it warms up ok when stationary but cant keep warm when running the thermostat is stuck open. If it's not been replaced in a long time it's not an easy job. Make sure you get the right one. Think it was 84 degree. 87 ones often sold that make the engine run a bit too warm & the cooling fan will keep coming on. Someone will correct this if my memories failed.

Old tip that works well is to drill an 1/8th hole in the rim of the stat, helps bleed the air out.

Ah splendid, thanks for all the replies.
I hadn't even thought about the thermostat as the car got warm in the first place.
Now I just feel stupid.

Thanks all I will investigate this and try to fix.

I love a swine of a job. Eeekkkkk.

Sorry to lower the tone folks but I think you missed a trick there. Did you not offer to warm her up through bodily heat? You know how the Eskimo's keep warm don't you?

might be worth pulling the2x fuses to the fans and seeing if the heating air temperature rises. If the radiator sensor is faulty it may be switching the fan on at too lower temperature. What does the guage read during normal running ?

Could be air in the system. The heating radiator circuit is the highest point in the cooling system but there was a recent thread with the same problem that turned out to be the thermostat .